gcse chemistry

• What type of structure does diamond have?

  Giant covalent structure
• What is an example of a simple covalent compound?

  Chlorine (Cl₂)
• Why do ionic compounds have high melting points?

  Due to strong electrostatic forces of attraction
• What is the formula for sodium iodide?

  NaI
• How do metallic bonds form?

  Through the attraction between positive ions and delocalised electrons
• What is the property of graphite that allows it to conduct electricity?

  Presence of delocalised electrons
• Why are polymers solid at room temperature?

  Due to strong intermolecular forces between molecules
• What is the melting point of diamond?

  3550°C
• What is the structure of ionic compounds?

  Giant ionic lattice
• How does the structure of graphite differ from diamond?

  Graphite has layers, while diamond does not
• What is the main use of diamond?

  Jewellery and cutting tools
• What is the reason for the high melting point of ionic compounds?

  Strong electrostatic forces require much energy
• What is the formula for silicon dioxide?

  SiO₂
• Why do metals conduct electricity?

  Due to free-moving delocalised electrons
• What is the property of silica regarding solubility?

  Insoluble in water
• What is the significance of the term 'allotropes' in carbon?

  Different physical forms of carbon exist
• What are the properties of polymers?

  • Large molecules with strong covalent bonds
  • Higher melting points than small molecules
  • Solids at room temperature
  • Do not conduct electricity
• What are the differences between diamond and graphite?

  • Diamond: Hard, no free electrons, high melting point
  • Graphite: Soft, conducts electricity, layers of atoms
• What are the characteristics of metallic bonding?

  • Positive metal ions in a sea of delocalised electrons
  • Strong electrostatic attraction
  • Good electrical and thermal conductors
  • High melting points
• What are the properties of ionic compounds?

  • High melting and boiling points
  • Conduct electricity when dissolved in water
  • Form a giant ionic lattice structure
  • Do not conduct electricity when solid
• What is the structure of silica?

  • Silicon bonded to four oxygen atoms
  • No free electrons
  • Very hard and insoluble in water
• What are the properties of graphite?

  • Soft and slippery
  • Good electrical conductor
  • High melting point
  • Layers held by weak forces
• What is the role of electrostatic attraction in ionic bonding?

  • Holds oppositely charged ions together
  • Acts in all directions within the compound
  • Requires significant energy to overcome
• What are the characteristics of nanoparticles?

  • Very high surface area to volume ratio
  • Unique properties compared to bulk materials
  • Used in various applications including medicine and electronics
• What is the structure of a giant metallic lattice?

  • Layers of positive metal ions
  • Surrounded by delocalised electrons
  • Strong electrostatic attraction between ions and electrons
• What is the significance of the melting and boiling points in covalent compounds?

  • Higher than simple covalent molecules
  • Due to stronger intermolecular forces
  • Important for understanding material properties
• What is the difference between simple molecular and giant covalent structures?

  • Simple molecular: small number of atoms, weaker forces
  • Giant covalent: large number of atoms, strong covalent bonds
• What are the properties of metals?

  • High melting and boiling points
  • Good conductors of heat and electricity
  • Malleable and ductile